The present invention relates to a silicone composition containing a low-viscosity oil as a base oil, and more particularly to a lactone-modified silicone composition that is very uniform and stable namely, one wherein no separation of components is observed, and a cosmetic agent or lustering agent containing it.
Conventionally, paste-like or grease-like materials containing a silicone oil as a main component have been used in many industries, and recently various wax-like compositions containing a low-viscosity silicone oil have been proposed in many industries, especially in the medical and cosmetic industries, because such a low-viscosity silicone oil is excellent in its smooth spreadability on human skin and its refereshing feeling when it is used, in addition to its good features of low toxicity and little skin irritation. In these wax-like compositions, a large amount of a thickening agent made of inorganic materials such as silica flour, kaolin, talc, sericite, bentonire, etc., or organic materials such as lithium soap, aluminium soap, etc. had to be blended to change a low-viscosity oil to a paste-like or grease-like material (examples of these thickening agents are shown in Silicone Resins, vol. 9, of Plastic Material Series, published by Nikkan Kogyo Shinbun-sha).
However, the use of a large amount of a thickening agent makes it difficult to get a smooth and uniform silicone composition. It has further been pointed out that separation of the silicone oil from the composition often occurs, and thus it fails to maintain its stability.
Wax-like compositions containing a low-viscosity silicone oil have generally also not been known, because the known synthetic or natural waxes are hydrocarbons or their ester compounds, and they are not compatible with a low-viscosity silicone oil, and thus the waxes and the silicone oil separate.
Accordingly, a silicone oil having a relatively high viscosity of not less than 100 cSt at 25.degree. C. have been used as a base oil. However, paste-like or grease-like silicone compositions using a silicone oil having a relatively high viscosity as a base oil cannot be smoothly spread, and often give a sticky feeling when they are used. Thus, it is considered that creams, sticks, ointments, or cake-like compositions using such silicone compositions did not have the needed qualities.